摘要
由衣康酸(IA)与环氧树脂E-51酯化反应合成了环氧衣康酸酯树脂(IE),再接枝不同结构的半封端异氰酸酯调控IE的光固化活性,制备了半封端异氰酸酯改性环氧衣康酸酯水性树脂(DIHIE)。采用红外(FT-IR)、核磁(^(1)H NMR)及激光粒度仪对产物的化学结构和水分散体粒径进行了表征。实验结果表明:反应物羧基与环氧基物质的量比为2∶1,于90℃下反应4 h,催化剂N,N-二甲基苄胺用量为体系反应物总量3%的条件下合成IE,IA转化率达到95%左右。以异佛尔酮二异氰酸酯(IPDI)和甲基丙烯酸羟乙酯(HEMA)合成半封端异氰酸酯中间体,再与IE反应得到IPDIHIE。合成IPDIHIE时,选择丙酮作为溶剂,在丙酮回流温度(56℃)下反应8 h即可反应完全,采用三乙醇胺(TEOA)作为中和剂,IPDIHIE水分散体的贮存稳定性较好。对DIHIE的漆膜性能进行分析,可发现DIHIE的光固化活性明显提高,固化时间由改性前的100 s缩短至60 s以内,漆膜铅笔硬度可达4H,附着力表现优异,均在1级左右。
Epoxy itaconate resin(IE)was synthesized by esterification of itaconic acid(IA)with epoxy resin E51.The IE was then reacted with different half-terminated isocyanates to prepare epoxy itaconate resin modified with isocyanate(DIHIE)in order to improve the UV curing activity.In next,the chemical structure and particle size distribution of IE and DIHIE were characterized by FT-IR,^(1)H NMR and laser particle sizer.The results showed when the molar ratio of carboxyl group to epoxy group was 2∶1,the reaction temperature and time was 90℃for 4 h,and the amount of catalyst N,N-dimethylbenzylamine was 3%of the total amount of reactants,while the conversion rate of the IA was about 95%.The half-terminated isocyanate intermediate was synthesized from isophorone diisocyanate(IPDI)and hydroxyethyl methacrylate(HEMA),and then it reacted with IE to obtain IPDIHIE.IPDIHIE was synthesized with acetone as solvent,which was carried out at acetone reflux temperature(56℃)for 8 h.The storage stability of the DIHIE dispersion was better when triethanolamine(TEOA)was used as neutralizing agent.The UV curing activity of the resins were improved obviously after being modified by half-terminated isocyanate.The curing time was shortened from 100 s to less than 60 s after modification.The pencil hardness of paint film could reach 4H and the adhesion performance was excellent.Moreover,all of them were about 1 grade.
作者
边均娜
陈健
杨兆哲
吴国民
孔振武
BIAN Junna;CHEN Jian;YANG Zhaozhe;WU Guomin;KONG Zhenwu(Institute of Chemical Industry of Forest Products,CAF,National Engineering Lab.for Biomass Chemical UtilizationF,Key Lab.of Chemical Engineering of Forest Products,National Forestry and Grassland AdministrationF,Key Lab.of Biomass Energy and Material,Jiangsu Province,Nanjing 210042,China;Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University,Nanjing 210037,China)
出处
《林产化学与工业》
CAS
CSCD
北大核心
2022年第2期101-109,共9页
Chemistry and Industry of Forest Products
基金
中国林科院中央级公益性科研院所基本科研业务费专项资金重点项目(CAFYBB2020GA001)。
